GEO-GREEN designs and installs geothermal systems. The choice of systems (open or closed geothermal system) and material (probes and heat pumps), sizing and placement will depend on your requirements, your building and the nature of your subsoil.
Exclusively to GEO-GREEN: the slanting placement of probes in closed loop systems for yet more benefits.
GEO-GREEN assists you and studies your project with you in order to find the optimal tailor-made solution. But GEO-GREEN also has several years of expertise in soil remediation, emptying of tanks, and in the making of wells in order to have supplies of water.
Closed geothermal system
The closed geothermal system is certainly the core of GEO-GREEN's activities. With GEO-GREEN, you will have the advantage of great technical expertise and an in-depth knowledge of geology and construction.
Design of the geothermal system
At GEO-GREEN, the design of the geothermal system is carried out by an expert in hydrogeology who has more than 20 years' experience. During his study he takes into account a number of criteria such as:
- The power of the heat pump (HP).
- The running time of the system.
- The PF (Performance Factor). This is measured according to a standard procedure and shows the relationship between the heat energy produced, expressed in kW, and the electrical energy consumed by the operation of the HP. Geothermal HPs (ground - water) have a PF which lies between 4 and 5. This indicates that for 1 kW electric energy injected into the pump (to operate the compressor), it returns between 4 and 5 kW. That is, 3 to 4 kW gained... thanks to geothermal probes!
- By way of comparison, air source HPs have a much lower PF, around 3. An air source HP is therefore going to consume a lot more electricity in order to produce an identical output.
- The SPF (Seasonal Performance Factor) expresses the average output of the PF over 12 months and gives the annual performance of your installation.
- The geology, that is the nature of the subsoil from which the calories will be extracted. There can be a fivefold (5x) gap between the thermal characteristics of the geological formations, depending on their nature. In soft soil, for example, sand has a better capacity than clay. In stones, limestone is better than shale rock.
- The hydrogeology which enables the presence of groundwater tables to be analysed and their flow studied. Water flows can have a very positive impact on the conductivity of the probes. Knowing the hydrogeological environment well is therefore essential for calculating adequate performance on a case-by-case basis.
- The choice of type of geothermal probe (Polyethylene (PE), stainless steel, coaxial, double U, vertical, sloping etc.), the drilling diameter, the total length of the probes or the quality of their placement in order to ensure maximum grip with the ground, also play a part in the final performance of the system!
- The heat transfer fluid to use: classic or biodegradable glycol water, tap water, beetroot juice etc....... there are several solutions.
Only a professional geologist can work out the precise sizing of a geothermal system!
Assisting with your project
GEO-GREEN assists you throughout your project. Whether it is a question of applying for a permit or advising you on the choice of one or another technology, GEO-GREEN is always there!
GEO-GREEN can also help you analyse the various possible heating solutions: oil, gas, geothermal HP, air source HP and compare the cost-effectiveness of the various options, taking into account the investment, annual running costs and, where applicable, subsidies and tax advantages. And all this tailor-made to your personal situation.
A team of experienced technicians carry out the installation of the system, namely:
- the drilling or vibro-sinking,
- the placement of the probes,
- the horizontal links to connect the probes to a collector which is itself connected to the building's boiler room,
- the placement of the heat transfer fluid,
- the pressurisation of the system.
In addition, GEO-GREEN has modern, very compact, technical equipment which enable it to access almost any place.
In collaboration with the heating company or the consultancy firm, GEO-GREEN starts up the system, regulating the flow in each of the probes.
The thermal response test (TRT)
GEO-GREEN also offers, depending on requirements, to measure the intrinsic characteristics of the ground and the geothermal probe at the precise place where it is inserted.
Once the geothermal probe is installed, it is connected to the measuring device which circulates the heated water with a calibrated energy. Continuous measurements of the temperature on entering and leaving the probe enable the way in which the soil is behaving to be studied. This phase lasts between 3 and 5 days. Once the data has been recorded, the thermal coefficient of the probe, lambda (expressed in W/mK), is determined.
The value of the thermal coefficient is then used to determine the size of a probe field by means of suitable software. This work is specifically carried out for large buildings, with geocooling, for example.
This measurement thus enables the reliability and sustained operation of the geothermal system to be guaranteed.
GEO-GREEN has more than twenty years' experience in soil remediation and contaminated groundwater tables.
GEO-GREEN sets up simple or complex soil remediation systems such as:
- the excavation of contaminated earth,
- the excavation of contaminated earth with shoring up systems,
- water pumping and carrying out adequate treatment
- the injection of products to destroy the contamination or promote rapid degradation.
Emptying of tanks
GEO-GREEN removes and empties your buried and no longer used tank in accordance with current legislation.
The creation of water wells
You must supply a rainwater tank, a room or a heat pump in an open geothermal system.
Setting up a well requires skills in geology and in particular in hydrogeology. GEO-GREEN can carry out:
- the feasibility study for the project,
- the request for a permit,
- the placement of the infrastructure,
- the pumping tests which determine the hydraulic capacity of the well.
Geo-Green has powerful and up-to-date equipment enabling them to drill a water well down to a depth of several tens of metres.